Index: mlir/lib/Analysis/DataFlow/ConstantPropagationAnalysis.cpp
===================================================================
--- mlir/lib/Analysis/DataFlow/ConstantPropagationAnalysis.cpp
+++ mlir/lib/Analysis/DataFlow/ConstantPropagationAnalysis.cpp
@@ -38,8 +38,10 @@
   // guarantee that folding will be out-of-place. We don't allow in-place
   // folds as the desire here is for simulated execution, and not general
   // folding.
-  if (op->getNumRegions())
+  if (op->getNumRegions()) {
+    markAllPessimisticFixpoint(results);
     return;
+  }
 
   SmallVector<Attribute, 8> constantOperands;
   constantOperands.reserve(op->getNumOperands());